Dishwasher



y 0, 1955 R c. GEIGER ETAL DISHWASHER 2 Sheets-Sheet 1 Filed Oct. 11, 1949 FILL VALVE SOLENOID 756 f DRAIN VALVE SOLENOID United States Patent DISHWASHER Russell C. Geiger and David A. Meeker, Troy, Ohio, as-

signor to The Hobart Manufacturing Company, Troy, Ohio, a corporation of Ohio Application October 11, 1949, Serial No. 120,656 8 Claims. (Cl. 134-58) This invention relates to dishwashers and more par ticularly to such machines which are adapted for household use and for use in smaller commercial establishments.

In a dishwasher particularly adapted for household or domestic use it is desirable to provide a washing chamber in which the articles to be washed are received and to which access can be obtained whenever desired. Thai is, the washing chamber is provided with a door which is closed when the articles have been placed therein, and which normally remains closed throughout the washing cycle. However, if after the cycle has started, additional articles are discovered which require washing, it is desirable to enable the user to open the chamber and include the additional articles, rather than to have the machine definitely continue throughout its full cycle before such access can be obtained.

The present invention makes it possible to open the door and to include or remove articles as may be desired at any point in the cycle, the progress of the washing cycle being interrupted for only the period of time during which the door is open. This prevents the splashing of washing fluid outside of the machine, and also makes it possible for the user to view the articles in the chamber without interference from either wash or rinse supplies of fluid. Thereupon, and following the closing of the door, the cycle is resumed at the point at which it was interrupted, and continues to completion in the normal way.

While it is desirable to interrupt the cycle in the manner just described and to prevent supply of washing fluid to the chamber during the time the door is open, it is undesirable to completely deenergize the system since that may lead to loss of the body of washing fluid already in the chamber, or otherwise interfere with the proper resumption of the cycle. For example a solenoid operated drain valve may be provided which opens when not energized, and if such valve were deenergized upon the opening of the door, the drain would open and the body of water would be unnecessarily lost. The invention assures that the drain valve will be maintained in closed position, if it was closed at the time the door was opened, and proper controls are provided so that while the supply of additional fluid will be stopped, the fluid already there will not be discharged, merely because of such opening of the door.

Likewise it-is desirable to afford an indication to the user that the washing cycle is in progress, and to continue such indication during the time that the door is open. Thus when the door is opened initially to receive the articles to be washed, and prior to the beginning of the actual washing cycle, there is no indication and the user is free to open or close the door as desired. However after the cycle has been started by actuation of a manual control member, an indication is shown of that fact. The user is free to open the door at any time during the course of the cycle, but such intermediate-door opening does not change the indication, which thus persists and continues to direct attention to the fact that the operation is in progress, though temporarily interrupted by the door opening. It is only upon the final conclusion of the entire washing and rinsing cycle that the manual control is restored to its initial or inoperative position, and the indication withdrawn.

Further in accordance with the invention, a sequence timer controls the operations through a series of washing steps, including an initial wash, followed by one or more rinse operations in which fresh fluid is supplied, and this in turn is followed by a drying step in which, after the final rinsing operation and the discharge or drain of the wash fluid from the chamber, a flow of air is produced by a fan located in a housing beneath the chamber and passed over a heating unit, such hot air flow being introduced along the lower side of the chamber and flowing across the articles to produce an effective drying thereof before the cycle is finally completed. The cycle thus proceeds in accordance with the predetermined sequence, and without necessity for intermediate attention, providing for the washing and drying of the articles, such as the dishes, as a single coordinated operation.

It is therefore the principal object of the invention to provide a dishwasher of this character, and one which is simple to operate, economical, and and satisfactory in use.

Other objects and advantages will be apparent from the following description, the accompanying drawings, and the appended claims.

In the drawings- Fig. l is a view in front elevation of a dishwasher constructed in accordance with the present invention with a portion of the front panel broken out to show the mechamsm;

Fig. 2 is a vertical sectional view through the side wall substantially on the line 22 of Fig. 1 with parts of the chamber broken away to show the operating mechanism;

Fig. 3 is a partial horizontal sectional view through the door handle showing the operating mechanism associated therewith;

Fig. 4 is a fragmentary section substantially on the line 4-4 of Fig. 1 showing the seal around the top and sides of the door with the door partly open;

Fig. 5 is a detail sectional view through the bottom of the door showing the path for the escape of the drying flow of air.

Fig. 6 is a rear elevational view showing the housing for supplying the heated air for drying; and

Fig. 7 is a diagrammatic view illustrating the control mechanism.

Referring to the drawings, which illustrate a preferred embodiment of the invention, the dishwasher includes an outer cabinet shell 10 mounted on a supporting base 11 and having a top 12 with a splasher back 13 preferably integral therewith. An inner shell or casing 15 encloses and defines the washing chamber shown at which is adapted to receive the dishes or articles to be washed. A lower shell or casing 22 defines a sump 25 at the lower side of the washing chamber 20 into which the washing fluid drains during the washing operation. At the bottom of sump 25 there is a discharge valve 27 controlling the discharge of the liquid into a drain 28 and provided with a strainer assembly 29, the discharge being controlled by a valve lever 30 normally biased to downward or valve opening position by means of spring arm 31. The valve is arranged to be held in closed position upon the actuation of a solenoid 32 having a yieldable spring connection 33 to the lever arm 36, the solenoid when engaged overcoming the efifect of spring 31 drawing the valve into its closed position, and an overflow tube highly advantageous 34 extends upwardly from the valve as indicated in dotted lines in Fig. 2.

The washing fluid is recirculated by means of a pump 35 having its inlet 36 communicating with the lower part of the sump and driven by an electric motor 37. It supplies the fluid under pressure to the rotatable wash arm 38 from which it is sprayed upon the articles supported in the racks 40 and 41 within the washing chamber.

A door 44 is provided for the washing chamber which is pivoted on the axis 45 adjacent the lower edge of the door. Lever arms 46 are connected to the door at each side thereof and to balance springs 47, and an adjustable stop 48 is provided at each side of the cabinet in position to engage the end of the adjacent lever 46 when the door has been swung to its open position through an angle of about 90".

A handle 50 is provided for actuating the door, the handle providing for locking the door in its closed position and being rotatable about the axis of shaft 51 to release the latch and allow the opening of the door. Any suitable construction may be provided as desired, that shown comprising a pair of pins 53 working into levers 54 which act to spread locking bars SSagainst the action of spring 56 connecting their adjacent ends and tending to draw them together and into position where the latch is released. The ends of the bars are guided on the frame of the door as shown at 58 and carry latching members 60 which fit into keepers fastened to the door frame so that when the handle is turned to the position shown in Fig. 1 the bars 55 will be expanded outwardly in the position shown in Fig. 3 to latch into engagement with the keepers 61 and thus securely retain the door in closed and sealed position.

Upon twisting of the handle the spring 56 withdraws the latch bars, and the door can then be freely swung to its open position. The latch mechanism is located within and protected by the inner door liner 62.

In order to provide for the filling of the wash chamher with the desired quantity of water for washing and rinsing purposes, a supply line of fresh hot water is connected as shown at 65 and a constant flow valve 66 controlled by solenoid 67 is provided so that the valve can be opened for a definite period of time to allow a proper amount of water to flow through line 68 and into the washing chamber, to provide the desired quantity of liquid therein.

The various steps in the washing cycle are controlled by a sequence timer indicated generally by reference numeral 70. The timer embodies an electric motor 71 and a dial 72 which is located on the front of the machine in position where it can be seen by the user and is suitably marked such as Wash, Rinse, Dry and Off so that the operator can determine at all times at what point in the cycle the machine is operating. The timer incorporates a number of different circuits each of which can be arranged to be closed and opened for any desired interval and at any point in the cycle.

Operation of the machine is initiated by a manual control member shown at 75 in the form of a button at one side of the door which is connected to a push rod 76 that is normally spring biased as shown at 77 to its upper or inoperative position. When manually displaced, however, the push rod operates through a link or lever 78 to close contacts 80 which control the operation of the timer motor '71 and thus the timer motor begins to operate. As soon as this motor 71 is operating, it remains in operation independently of the push rod throughout the entire washing, rinsing and drying cycle, holding the switch 80 closed and controlling the several other switches for these operations through suitable cams indicated at in Fig. 7. Thus as soon as the timer motor 71 is in operation and the push button is released, spring 77 restores the push rod to its inoperative position, and the timer itself holds the switch 80 closed until the full cycle of the machine is completed.

In addition to providing a washing cycle and one or more rinse cycles, it is desirable to provide for the drying of the fully washed dishes, and for this purpose a flow of heated air is introduced into the washing chamber along the lower side wall thereof. A flange is provided which is closed against the chamber wall at its upper side but open at its lower side as indicated at 91. This forms a passage which communicates with a chamber 92 formed by plate 93 secured to the rear wall of the washing chamber and extending downwardly to connect with a housing 95 which is located below the washing chamber and to one side of the sump casing 22. A heater unit indicated as a cone type electric heater 96 is mounted in housing 95 and a flow of air is provided by a fan 100 driven by an electric motor 301. The fan thus develops a flow of air through the housing and over the surface of heater 96 which heats tr e air and increases its drying capacity, such heated air then being introduced into the washing chamber through the rearward slot 91 from which it is allowed to fiow over the dishes in the chamber, being vented through the passage 102 below the lower edge of the door 40.

In order to prevent discharge of water through passage 102, it will be noted in Fig. 5 that the lower shell 22 is formed to provide an upwardly extending baffle portion 103 which projects above the level of the passage 102 and substantially above the level of the upper end of the overflow tube 34. This baffle portion 103 has an inturned upper edge, and it is overhung by the lower portion of the inner door liner 62 in the closed position of the door 44. A rubber seal 104 (Fig. 5) is provided on the inturned flange along the portion of shell 10 just below the door and engages the front surface of baffle 103 to seal the portion of the cabinet containing the electrical parts against moisture from the washing chamber.

Additional seals are provided along the sides and top edges of the door to prevent discharge of the water from the washer chamber 20 around the edges of the door. Referring to Fig. 4, the sealing strip for the cabinet includes a rear portion 105 bolted to the shell 15 at 106, and the forward portion 107 of this strip is inwardly offset with respect to the portion 105 to form a forwardly projecting flange. A cooperating sealing strip 108 is screwed to the door liner 62 at 109 and projects inwardly therefrom to form a flange adapted to overlap the outer surface of the flange 107 in the closed position of the door. These flanges are proportioned to provide working clear ance between their overlapping surfaces, a clearance of the order of inch having been found satisfactory. Also, the flange 108 is shown as slightly wider than the flange 107, a difference of inch being satisfactory, and the stops 43 can be adjusted as required to locate the door in closed position with the inner edge of strip 108 just in contact with the offset portion of strip iii5-lil7.

This sealing arrangement is thus very simple in construction, and it is so located with respect to the door 44 and the forward edge of the chamber 15 as to provide highly effective sealing against leakage past the door and also to cause any liquid which does escape beyond the flanges 107 and 108 to be returned to the washing cham her. As shown in Fig. 4, the flange 107 is located well within the front of the chamber in rearwardly spaced relation with the forward edge of the shell 15, and also the flange 108 is located at the rearmost portion of the door and beyond the curved portion of the door liner 62. Thus the seal provided by the flanges 107 and 108 is not located at a corner of the washing chamber, and hence the tendency is avoided for hydraulic pressure to be built up in the area of the seal in such manner as would be the case, for example, if streams of water from different directions were concentrated at the curved portion of the liner 62 shown in Fig. 4.

It is desirable to prevent the opening of the door during the time that the wash sprays are being projected upon the dishes but it is also desirable to make it possible to open the chamber even after the cycle has started to permit the addition to or withdrawal from of articles from the chamber. If the entire system is deenergized, the drain valve will be allowed to open under the action of its spring 31, and thus the body of Wash water then in the chamber would be lost unnecessarily. In order to provide the desired protection for the operator while avoiding such undesirable loss of washing liquid, a control is incorporated for preventing the deenergizing of the drain valve in response to the opening of the door, maintaining that valve in energized and closed position if it was closed at the time the door was open. The fill valve however and the motors operating the pump or fan are definitely deenergized so that whichever of them may have been energized and operating when the door was opened, will be definitely deenergized.

For this purpose a switch 110 is mounted on the casing by means of a bracket 111, with its actuating part 112 in position to be engaged by the adjacent door latch when the same is in latching position. However upon the turning of the handle 50 to release the door, but prior to any actual opening of the door, the circuit of this switch is opened, to accomplish the results described above.

An indicating means is likewise provided which may be in the form of a light 115 and jewel lens 116 which are located in position adjacent the manual control and afford an indication that the washing cycle is in progress. It is desirable that such indication continue even though the door has been opened, thus affording definite indication that the cycle is under way, as distinguished from the opening of the door prior to the beginning of the cycle when the articles are first placed in the machine.

The circuits by means of which the above controls are accomplished are illustrated in Fig. 7. As shown a power supply is indicated at 120, 121, line 121 being connected through line 122 serving as common supply line to one side of the timer circuit.

At the beginning of a cycle, it is necessary first to close the door 44, thereby closing switch and establishing a circuit from line 120, line 123, through switch 110 and line 124 to the common connection point 125. Connection is made from this point through line 126 to the timer motor 71, and hence upon actuation of manual push button 75, timer switch 80 is closed and the cycle begins, the push button being then returned to its normal position by spring 77 in the manner described above and the switch 80 being held closed by operation of the cams 85. A parallel circuit is also established through line 128 to indicator which thus affords an indication that the cycle is in progress.

The first operation is to close the drain valve 27, this being accomplished by the timer closing its contacts 130 which energizes solenoid 32 through lines 131 and 132. Simultaneously therewith the fill valve solenoid 67 is energized by the closing of the time contacts 135 which energizes solenoid 67 through lines 136 and 137. Switch 135 opens after a predetermined interval such that the proper amount of wash fluid has been introduced, the switch 130 remaining closed to keep the drain valve in closed position. Practically simultaneously with the opening of switch 135, the timer closes its switch contact 140 and this energizes the pump motor 37 through lines 141 and 142. A proper amount of washing compound having been placed in the chamber, the first step of the washing operation with the pump recirculating the wash fluid for a length of time as determined by the setting of the time to eflectively wash the articles.

At the end of that interval the timer opens its contacts 130 and 140, stopping the pump and allowing the drain valve to open under the action of its spring thus draining out. the wash fluid. Thereafter a rinse cycle is carried out, the pump motor again being energized and the till valve 6 and drain valve solenoids likewise being energized through proper setting and timing of the operation of switches 130, 135 and 140 to provide for the proper amount of rinse water, and the discharge thereof after a predetermined time interval.

Finally, at the end of the rinse operation, timer switch 130 is opened draining the wash chamber and timer switch is closed thereby energizing the fan motor 101 and the heater 96 through lines 151, 152. This supplies 1.: a flow of heated air for drying the dishes, this being continued for a predetermined interval such as to effect substantially complete drying of the dishes as well as the entire interior of the chamber itself. inally the timer motor 71 releases timer switch 30, allowing this switch to open and thereupon stopping the timer motor itself.

if the operator should desire to open the chamber at some intermediate point in the cycle, such as immediately after the beginning of the cycle and while the fill valve is open or the pump is in operation, it is possible to do so, the system functioning in the following manner. Immediately upon the turning of the handle 50 to unlatch the door, the latch 61 is withdrawn from the switch button 112, which thereupon opens and in doing so deenergizes the contact terminal 125. Thus the energizing circuit for the solenoid 67 and for the pump motor 3'7 are both broken immediately upon the unlocking of the handle and prior to the actual opening of the door, and as a result there is no splashing or loss of wash fluid when the door is actually opened.

It will be evident, however, that the circuit for the drain valve solenoid 32 is not completed through the terminal 125 but directly from line 12* and therefore this solenoid remains energized when the door is opened, preventing the opening or the drain valve and avoiding loss of the body of fluid already in the chamber. The timer motor stops for the period that the door is opened, but immediately resumes operation upon the subsequent closing of the door, thus assuring that the cycle will resume at the same point at which it was interrupted, and

continue on through the same sequence. it will also be seen that the indicator 115 remains operated throughout the opening and closing of the door, thus indicating to the user that the cycle has not been completed.

A similar result occurs in the event that the door should be opened during the rinse or the drying portions of the cycle, namely, the drying operation is stopped, it it was in progress at the time the door was opened, and resumes after the door is closed.

From the above it will be evident that the system is I highly flexible, permitting the operator to open the door rinsing and drying of the dishes.

Cross reference is made to our copending application Serial No. 120,655 filed of even date herewith, now Patent No. 2,681,658, dated June 22, 1954.

While the form of apparatus herein described constitutes a preferred embodiment of the invention, it is to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

l. A dish washing machine including a cabinet having a washing chamber and fluid distributing means therein, a door for said chamber adapted to be opened at any point in the washing cycle, a sequence timer for controlling the operations in said cycle, a switch for interrupting operation of said timer, a sealing flange secured within said chamber and extending outwardly therefrom towards said door, a cooperating flange projecting inwardly from the inner face of said door and adapted to overlap the outer surface of said sealing flange to prevent the discharge of fluid around the periphery of said door during the washing cycle, a single locking handle for said door, means supporting said switch in said cabinet outwardly of said sealing flange, and means directly controlled by movement of said handle from locked to unlocked position to operate said switch simultaneously with unlocking of said handle and prior to the opening of said door.

2. In a dishwasher having a washing chamber having an opening in the front thereof and adapted to receive articles therein, a door for said chamber hinged within said opening along the lower edge thereof, means for supplying washing fluid to said articles, an overflow tube for washing fluid in said chamber, means for directing a flow of heated air upon said articles following the washing operation, means forming a slot between the bottom of said opening and the lower edge of said door for free discharge of said heated air from said chamber, a bafiie extending upwardly in said chamber adjacent said slot to a position above said slot and above the upper end of said overflow tube to provide for flow of. said heated air above said battle to said slot while preventing discharge of fluid from said chamber through said slot, and cooperating flanges on said door and in said chamber adapted to overlap in the closed position of said door to prevent discharge of fluid from said chamber.

3. In a dishwasher having a washing chamber having an opening in the front thereof and adapted to receive articles therein, a door for said chamber hinged within said opening along the lower edge thereof, means for supplying washing fluid to said articles, an overflow tube for Washing fluid in said chamber, means for directing a flow of heated air upon said articles following the washing operation, means forming a slot between the bottom of said opening and the lower edge of said door for 1 free discharge of said heated air from said chamber, a baflle extending upwardly in said chamber adjacent said slot to a position above said slot and above the upper end of said overflow tube, said door including an inner liner adapted to extend inwardly in overhanging spaced for washing fluid in said chamber, means for directing a flow of heated air upon said articles following the washing operation, means forming a slot between the bottom of said opening and the lower edge of said door for free discharge of said heated air from said chamber, a baflle extending upwardly in said chamber adjacent said slot to a position above said slot and above the upper end of said overflow tube, said door including an inner liner adapted to extend inwardly in overhanging spaced relation with said baffle in the closed position of said door for cooperation with said baflie to provide for flow of said heated air to said slot while preventing discharge of fluid from said chamber through said slot, and cooperating flanges along the sides and top of said door and in said chamber to overlap in the closed position of said door to seal against discharge of fluid from said chamber.

5. A dishwasher including a casing having a washing chamber therein for receiving articles to be washed and having an opening in the front thereof into said chamber, a door for said chamber hinged within said opening along the lower edge thereof, means for supplying washing fluid to said chamber, an inner shell forming a sump for said chamber, an overflow tube for washing fluid in said front of said casing to form therewith a compartment 8 adapted to receive electrical control means for operating said dishwasher, means for directing a flow of heated air upon said articles following the washing operation, means forming a slot in said opening between the lower edge of said door and the adjacent portion of said casing for free discharge of said heated air from said chamber, a baffle extending upwardly from said inner shell adjacent said slot to a position above said slot and above the upper end of said overflow tube to provide for flow of said heated air above said baffle to said slot while preventing discharge of fluid from said chamber through said slot, and sealing means mounted on said casing along the lower edge of said slot in engagement with the front surface of said baffle to seal against passage of moisture from within said washing chamber to said compartment.

6. In a dishwasher including an outer cabinet, the combination of a shell defining a washing chamber within said cabinet for receiving articles to be washed and having a front opening, a door for said opening hinged to said cabinet along the lower edge thereof, said door including a portion extending inwardly of said chamber substantially beyond the forward edge of said shell in the closed position of said door, a sealing flange secured to said shell at a position located substantially inwardly of said chambar from said forward edge of said shell and projecting forwardly along the top and sides of said opening, a cooperating flange projecting inwardly of said chamber from the innermost portion of said door in position to overlap the outer surface of said sealing flange to prevent the discharge of fluid around the periphery of said door during the washing cycle, a single locking handle for said door, a sequence timer for controlling the operations of said dishwasher, a switch for interrupting operation of said timer to stop the application of fluid to said articles, means supporting said switch in said cabinet outwardly of said sealing flange, and means directly controlled by movement of said handle from locked to unlocked position to operate said switch simultaneously with unlocking of said handle and thereby to stop the application of fluid to said articles prior to the opening of said door.

7. In a dishwashing machine including a cabinet, a casing mounted in said cabinet having an opening in the front thereof and forming a washing chamber adapted to receive therein the articles to be washed, the combination of a door hinged within said opening, means for supplying Washing fluid to said articles, a sequence timer for controlling the washing cycle, a drain valve for said chamber, means controlled by said timer for opening and closing said drain valve at predetermined points in the washing cycle, a latching member for said door carried by said door, a keeper for said latching member located in said cabinet adjacent said opening and adapted to receive said latching member in the latched position thereof, a handle on said door for shifting said latching member between the latched and unlatched positions thereof, a switch having an operating member, means mounting said switch in said cabinet adjacent said keeper and with said operating member in the path of movement of said latching member for operation by said latching member upon movement thereof between the latched and unlatched positions thereof, means connecting said switch with said timer and with said fluid supplying means to stop said timer and terminate the supply of washing fluid upon movement of said latching member away from said switch operating member to the unlatched position thereof and to resume operation of said timer and said fluid supplying means upon movement of said handle shifting said latching member into the latched position thereof, and means forming a circuit bypassing said switch to said drain valve causing said drain valve to remain in the position established by said timer upon the stopping of said timer by said switch.

8. In a dishwashing machine including a cabinet, a casing mounted in said cabinet and forming a washing chamber having an opening in the front thereof, the

combination of a door hinged within said opening, means for supplying washing fluid to the articles in saidchamber to be washed, a sequence timer for controlling the washing cycle, a drain valve for said chamber, means controlled by said timer for opening and closing said valve at predetermined points in the washing cycle, a latching member carried by said door, a keeper for said latching member located in said cabinet adjacent said opening for receiving said latching member in the latched position thereof, a handle on said door for shifting said latching member between the latched and unlatched positions thereof, a switch having an operating member, means mounting said switch in said cabinet adjacent said keeper and with said operating member in position for operation by said latching member upon movement thereof between the latched and unlatched positions thereof, a sealing flange secured within said chamber and extending outwardly therefrom towards said door from a position located inwardly of said switch,

a cooperating flange projecting inwardly from said door and adapted to overlap the outer surface of said sealing flange in the closed position of said door to protect said switch from fluid during the Washing cycle, means connecting said switch with said timer and with said fluid supplying means to stop said timer and terminate the supply of washing fluid upon movement of said latching member away from said switch operating member to the unlatched position thereof and to resume operation of said timer and said fluid supplying means upon movement of said handle shifting said latching member into the latched position thereof, and means forming a circuit bypassing said switch to said drain valve causing said drain valve to remain in the position established by said timer upon the stopping of said timer by said switch.

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